Wpf 多绑定命令参数

Wpf 多绑定命令参数,wpf,data-binding,mvvm-light,multibinding,relaycommand,Wpf,Data Binding,Mvvm Light,Multibinding,Relaycommand,因此,我为每个单独的listview项都有一个上下文菜单,listview绑定到一个用户列表。上下文菜单有一个子菜单,该子菜单绑定到可观察的用户状态集合。我希望能够将列表视图中的用户id和上下文菜单中的新状态id传递给我的更新命令参数。我只是研究了多重绑定,并相信这可能是一个很好的长期解决方案,我可以在其他地方使用。下面是一些代码: 用户视图中的列表视图: <ListView Background="Transparent" ItemsSource="{Binding UserList}"

因此,我为每个单独的listview项都有一个上下文菜单,listview绑定到一个用户列表。上下文菜单有一个子菜单,该子菜单绑定到可观察的用户状态集合。我希望能够将列表视图中的用户id和上下文菜单中的新状态id传递给我的更新命令参数。我只是研究了多重绑定,并相信这可能是一个很好的长期解决方案,我可以在其他地方使用。下面是一些代码:

用户视图中的列表视图:

<ListView Background="Transparent" ItemsSource="{Binding UserList}" SelectionMode="Single">
    <ListView.Resources>
        <ContextMenu x:Key="Menu" DataContext="{Binding Path=PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
            <MenuItem Name="UserID" Header="{Binding UserID}"/>
                <Separator></Separator>
                    <MenuItem Header="Status" ItemsSource="{Binding DataContext.UserStatus, RelativeSource={RelativeSource FindAncestor, AncestorType=UserControl}}"
                              DisplayMemberPath="Name" Name="StatusID">
                        <MenuItem.ItemContainerStyle>
                            <Style TargetType="MenuItem">
                                <Setter Property="Command" Value="{Binding DataContext.UpdateDriverStatus, RelativeSource={RelativeSource FindAncestor, AncestorType=UserControl}}" />
                                <Setter Property="CommandParameter" Value="{Binding}" />
                            </Style>

                        </MenuItem.ItemContainerStyle>
                        <MenuItem.CommandParameter>
                            <MultiBinding Converter="{StaticResource MultiBindConverter}">
                                <Binding ElementName="DriverID"></Binding>
                                <Binding ElementName="StatusID"></Binding>
                            </MultiBinding>
                        </MenuItem.CommandParameter>                        </MenuItem>
                </ContextMenu>
            </ListView.Resources>

            <ListView.ItemContainerStyle>
                <Style TargetType="{x:Type ListViewItem}">
                    <Setter Property="ContextMenu" Value="{StaticResource Menu}" />
                </Style>
            </ListView.ItemContainerStyle>
            <ListView.ItemTemplate>
                <ItemContainerTemplate>

                            <TextBlock Text="{Binding UserName}" >

                            </TextBlock>
                </ItemContainerTemplate>
            </ListView.ItemTemplate>
        </ListView>
public class UsersPanelVM : ViewModelBase, INotifyPropertyChanged
{
    public ObservableCollection<UserPanelItem> UserList { get; set; }
    public ObservableCollection<UserStatusList> UserStatus { get; set; }

    private readonly IUserService _userService;
    public IUserService UserService { get { return this._userService; } }

    public UsersPanelVM(IUserService userService)
    {
        this._userService = userService;

        var model = this.UserService.GetUsers();
        this.UserList = model.Users;
        var statusmodel = this.UserService.GetUserStatus();
        this.UserStatus = statusmodel.UserStatus;

        this.UpdateUserStatus = new RelayCommand<UserStatusList>((s) => UpdateStatus(1,s));
    }

    //The 1, above, is hard coded to test the method call, but ideally that should be the selected UserID

    private void UpdateStatus(int ID, UserStatusList s)
    {

    }

    public RelayCommand<UserStatusList> UpdateUserStatus { get; private set; }

}

用户虚拟机:

<ListView Background="Transparent" ItemsSource="{Binding UserList}" SelectionMode="Single">
    <ListView.Resources>
        <ContextMenu x:Key="Menu" DataContext="{Binding Path=PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
            <MenuItem Name="UserID" Header="{Binding UserID}"/>
                <Separator></Separator>
                    <MenuItem Header="Status" ItemsSource="{Binding DataContext.UserStatus, RelativeSource={RelativeSource FindAncestor, AncestorType=UserControl}}"
                              DisplayMemberPath="Name" Name="StatusID">
                        <MenuItem.ItemContainerStyle>
                            <Style TargetType="MenuItem">
                                <Setter Property="Command" Value="{Binding DataContext.UpdateDriverStatus, RelativeSource={RelativeSource FindAncestor, AncestorType=UserControl}}" />
                                <Setter Property="CommandParameter" Value="{Binding}" />
                            </Style>

                        </MenuItem.ItemContainerStyle>
                        <MenuItem.CommandParameter>
                            <MultiBinding Converter="{StaticResource MultiBindConverter}">
                                <Binding ElementName="DriverID"></Binding>
                                <Binding ElementName="StatusID"></Binding>
                            </MultiBinding>
                        </MenuItem.CommandParameter>                        </MenuItem>
                </ContextMenu>
            </ListView.Resources>

            <ListView.ItemContainerStyle>
                <Style TargetType="{x:Type ListViewItem}">
                    <Setter Property="ContextMenu" Value="{StaticResource Menu}" />
                </Style>
            </ListView.ItemContainerStyle>
            <ListView.ItemTemplate>
                <ItemContainerTemplate>

                            <TextBlock Text="{Binding UserName}" >

                            </TextBlock>
                </ItemContainerTemplate>
            </ListView.ItemTemplate>
        </ListView>
public class UsersPanelVM : ViewModelBase, INotifyPropertyChanged
{
    public ObservableCollection<UserPanelItem> UserList { get; set; }
    public ObservableCollection<UserStatusList> UserStatus { get; set; }

    private readonly IUserService _userService;
    public IUserService UserService { get { return this._userService; } }

    public UsersPanelVM(IUserService userService)
    {
        this._userService = userService;

        var model = this.UserService.GetUsers();
        this.UserList = model.Users;
        var statusmodel = this.UserService.GetUserStatus();
        this.UserStatus = statusmodel.UserStatus;

        this.UpdateUserStatus = new RelayCommand<UserStatusList>((s) => UpdateStatus(1,s));
    }

    //The 1, above, is hard coded to test the method call, but ideally that should be the selected UserID

    private void UpdateStatus(int ID, UserStatusList s)
    {

    }

    public RelayCommand<UserStatusList> UpdateUserStatus { get; private set; }

}
public类UsersPanelVM:ViewModelBase,INotifyPropertyChanged
{
公共ObservableCollection用户列表{get;set;}
公共ObservableCollection用户状态{get;set;}
专用只读IUserService\u userService;
公共IUserService UserService{get{返回此。\u UserService;}}
公共用户spanELVM(IUserService用户服务)
{
这是。_userService=userService;
var model=this.UserService.GetUsers();
this.UserList=model.Users;
var statusmodel=this.UserService.GetUserStatus();
this.UserStatus=statusmodel.UserStatus;
this.UpdateUserStatus=新的RelayCommand((s)=>UpdateStatus(1,s));
}
//上面的1是硬编码的,用于测试方法调用,但理想情况下应该是所选的UserID
私有void UpdateStatus(int-ID,UserStatusList)
{
}
public RelayCommand UpdateUserStatus{get;private set;}
}
我很确定我在这一点上100%迷失了方向

  • 正如我在您的另一个问题中所提到的,这是不必要的,因为您在对象模型中拥有除新状态之外的所有信息

    将命令和
    UpdateStatus
    方法移动到
    UserPanelItem
    的类中,该类也应保存您的ID,然后您只需将命令更改为:

    new RelayCommand(param => UpdateStatus(ID, (UserStatusList)param))
    
  • 如果您确实想这样做:再次设置父菜单项(其命令永远不会被使用)的
    CommandParameter
    ,将其移动到容器样式中的
    CommandParameter
    -
    Setter
    值,即

    <Setter Property="CommandParameter">
        <Setter.Value>
            <MultiBinding ...>
                ....
    
    
    ....